Need help troubleshooting my car

jamesbond007

Diamond Member
Dec 21, 2000
5,280
0
71
Hey guys! I need help trying to diagnose or fix a problem I've been having recently. For the last few days, my car seems to be turning over a bit harder than usual. When starting, the car has a slight 'shake' feel to it. It sounds like it barely wants to start. :(

Additionally, when I'm idling at a stop light, the car sounds like it sputters or is just about out of gas for a split second. There is a slight shake noticed at this point. Although I've never ran out of gas, it is similar to what it's like in the movies. :p It's nothing severe or as exaggerated as movies, but it sounds like the car just 'skips a beat'.

I was a bit low on gas, so I refueled it to make sure my guage wasn't malfunctioning. (neighbor at the lakes actually had that problem!) Anyways, while I was fueling, I checked under the hood and all my caps and lids seem tight and sealed well, so I shouldn't be losing any pressure in any of the obvious-to-see places.

As I'm typing this, I'm beginning to think it may be a misfire/bad spark plug perhaps? I checked my battery and it's a solid 12.4V or so while the engine is off and 14.38V while running and idling for a few minutes.

I'm not a grease monkey by any means, but if I can avoid having to take it into the shop, it'd sure help my wallet out. :D

Relevant Car Details:
  • 2003 Dodge Neon (SXT if that matters)
  • Just under 50,000 miles
  • New battery installed last winter
  • No accidents
  • Scheduled tune-ups performed as required
  • No previous engine problems

Thanks in advance!!!
~Travis
 

CrackRabbit

Lifer
Mar 30, 2001
16,642
62
91
Could be a number of things.
Plugs and wires are a good place to start, especially if they haven't been checked/replaced in a while.
Other things might be MAF/MAP sensor, IAC valve, EGR valve, fuel filter.
Might want to post this over in the forums at http://www.allpar.com lots of helpful mopar heads over there. :)
 

Fern

Elite Member
Sep 30, 2003
26,907
174
106
You may have gotten some bad gas.

I don't know how supplies are where you live, but I've happened to get some gas with a little water in it before when the station was low.

Fern
 

jamesbond007

Diamond Member
Dec 21, 2000
5,280
0
71
Originally posted by: Fern
You may have gotten some bad gas.

Yeah, but I found it was from Taco Bell! :D

Ok, sorry. How long would it take for bad gas to go through my car's system? I've been driving it for about....10 miles in-town so far since I filled up. (yeah, Fargo is SMALL compared to most other cities. ;))

CrackRabbit, I'm going to have a friend come over soon to help me check under the hood. He's my only car buddy, so we'll hopefully figure something out. If anything, I'm going to call my local shop tomorrow ASAP and have them check it out.

I really do hope it was only bad gas. There's no clanking of any kind and it's not audible with the windows down. It's like the car is shifting gears for a split second and like a rough shift. However, it does it a little when turning the engine over and even just idling. My friend says that the transmission should not be a concern. Phew...

Thanks guys!!!
 

jamesbond007

Diamond Member
Dec 21, 2000
5,280
0
71
Well my friend and I dinked around with the car last night. When he came over, I backed out of the garage and just let it idle and slowly crawl forward with my foot off the gas. It was the worst I have seen the situation - my car seemed to sputter and spatter, making my lights dim heavily! AHH! We noticed that anytime I put my foot on the brakes, the problem became exacerbated.

We unhooked the cables from the distributer block and took out the spark plugs and they all seemed fine. We also inspected the cables and they were tip-top as well. We then took a look at the air filter and that was really really clean as I had just recently had that changed anyways. We looked at a 'breather filter', as my friend calls it, but it sits in the same sealed container as the air filter. It sits in front of a small tube that goes directly to the engine block. We cleaned that a bit, but noticed that the hose that leads to the engine (or from, I'm not sure which way it flows) had a dark spot on it. My friend said that is probably oil. Is that normal?

We took the car out last night and drove it on the interstate and in town for about a half hour - everything seemed fine and it ran smooth. Come today, I drove it to the bank and had no problems. However, going to work from the bank was another story. The problem seems to still be there, but far less apparent than before. We're going to replace that breather filter tonight and see if that does anything. He said it's a cheap part to replace, so it's worth a shot before I bring it to the mechanics.

:: sigh ::
 

kalrith

Diamond Member
Aug 22, 2005
6,628
7
81
I had a somewhat similar problem. It seemed to be a gas issue, and it was intermittent. It would run great sometimes, but at other times it wouldn't start at all. It turned out to be a bad coil wire. We found out it was cracked by spraying down the wires with water from a squirt bottle while the car was running. This produced a nice light show and told us that there was a break in one of the wires. You might want to try this. Even if you don't get the light show, your plugs and/or wires could still be bad. How exactly did the plugs "seem fine"? Did you actually test them or just look at them? http://www.ehow.com/how_2060386_test-spark-plugs.html

Edit: Is the check-engine light on? If so, get it tested for free at AutoZone. It might say something very specific like misfire on cylinder #2. Misfires can be caused by vacuum leaks as well, so that could be a possible issue. Did you look to see if a hose just slipped off or something simple like that?
 

LTC8K6

Lifer
Mar 10, 2004
28,520
1,576
126
You could always put a bottle of HEET in and see if it helps. HEET will help if you have some water in your fuel. Or any decent brand of gas line antifreeze/water remover.
 

CrackRabbit

Lifer
Mar 30, 2001
16,642
62
91
If you are getting oil in your breather filter you might have a bad PCV (positive crankcase ventilation) valve. It might cause your car to run rough, but I'm not sure that is the case in your situation.
Its a cheap part ($10 at the most) and should be changed every 30-50k anyways. :)
 

Bignate603

Lifer
Sep 5, 2000
13,897
1
0
If you're noticing the problem more when you step on the brake my money is on a vacuum leak. You step on the brake and the booster starts using a bit more vacuum and it makes the problem work.